Hot answers tagged riichi-mahjong
I think most "official" rules will not allow you to do this. (For reference, I looked up the Japanese Mahjong rules from the European Mahjong association here.) In principle, I think swapping tiles that do not change the wait structure would be allowed, but it is impossible to verify. In your example of swapping the 5 for the 8, all that is visible is the ...
You replace them, because otherwise we will end up with five copies of the 5-numbered tiles, which is not the intention of using red fives.
Only top voted, non community-wiki answers of a minimum length are eligible